Startup Trademark Registration: Which Jurisdictions?

At least for the United States, early trademark protection is a must. A common mistake startups make is putting a lot of energy into developing their brand before they conduct a trademark search to find out what is already registered. The result? A company with thousands of dollars and hours invested needs to rebrand.

Identify your budget capabilities, then select the initial markets you intend to focus on. But remember: a small investment now can save you a lot more money later.

I would mirror what James has said. Early protection is also vital in the United Kingdom and Ireland where the 'first to use' principle is important. If you are going to launch in either the UK or Ireland, TM clearance searches are strongly recommended. The investment you make now in protecting your brand will pay off later, particularly if you monetise your registered rights by means of licensing.

I definitely agree with James and Niall - get your trademark registration in the countries of interest as soon as possible as others, particularly potential me-too competitors, may be quicker than you.
Since you are based here in Germany, you should clear the market by a trademark search, and then maybe start with a German mark. Within 6 months, you can use its priority (the application date) to get protection in other jurisdictions with the same priority date as well. Starting out with a Community Trademark (CTM or Gemeinschaftsmarke) is another option - it covers all 28 EU Member States. Switzerland and Japan can be added either by way of a so-called International Registration, or by filing national trademark applications. More questions - just let me know!